Ink Switchover from PK to MK

I have an Epson P600 with ConeColor Pro inks. I inadvertently switched to matte paper when the PK cartridge was too low. Now it won’t switch back from MK to PK.
I have a couple of ideas how to force it but I would prefer a proven approach before I corrupt a chip.

Yes, we have a notice about this on most/all of our P600 products. Here’s one with it.

You’ll need a new chip or use your Epson PK cartridge if it is not low or empty.